1. Field of the Invention
The present invention relates to a method and associated apparatus for biometric of identification of an individual using information obtained from unique portions of the eye which vary from individual to individual and are not readily observable in the absence of the individual voluntarily positioning the eye and eyelids and forebrows in a particular location.
2. Description of the Prior Art
It has been known to attempt to provide high-security personal identification systems for a wide variety of purposes including, but not limited to, identification of individuals for law enforcement purposes, limiting access to secure facilities and information and verification of an individual""s identity for other purposes when confirmation of identify is of great importance.
Among the known prior systems include the use of fingerprints, voice analysis, retinal scans and iris scans. Each of these approaches, while having some value, has inherent weaknesses. For example, fingerprint analysis is inherently insecure as copies of one""s fingerprints may be left in many areas where they can be lifted from an object and used to create a security breach. Also, with the large number of databases containing fingerprints, such as for law enforcement purposes, there may be undesired access to such fingerprints.
Voice identification techniques can be circumvented with high-fidelity recording equipment and also can be obtained from a targeted individual without the person being aware that a security-threatening event has occurred. Also, voice analysis cannot be used to generate a number that uniquely identifies an individual.
Retinal scanning, while tending to be secure, is somewhat limited in value as it requires that there be a clear view of the retina. Any opacification of the media from the cornea to the vitreous may severely decrease the accuracy of this approach. Also, iris scans that employ the morphology of the crypts in the iris can be circumvented by merely taking a picture of the target without the target being aware that a security-compromising event has occurred.
In spite of the foregoing, there remains a great need for an improved method of personal identification which resists unknown efforts to duplicate the identification information, is reliable and accurate, and avoids some of the difficulties in the hereinbefore described approaches.
The present invention provides a method and associated apparatus, which permits accurate biometric identification of an individual.
In one embodiment of the method, electromagnetic radiation is employed to illuminate the eye of an individual such that at least one portion of the eye selected from the group consisting of the perilimbal structure inferior to the cornea and the perilimbal structure superior to the cornea, is subjected to the radiation. The reflected radiation being received by a detector converts the light into corresponding acquired image information which may be introduced into a processor that has stored information regarding the individuals, with a comparison being effected to determine if a match exists. Output may be provided in various manners to provide the result in respect of whether or not a match identifying the individual has occurred.
In the preferred practice of the method of this invention, the perilimbal structure has a plurality of individual palisades and a plurality of interposed individual interpalisades. By monitoring a plurality of the palisades or interpalisades or both, each palisade or interpalisade may be assigned a value, which in the aggregate provides a unique identification of the particular individual. The physical parameters which are employed may include the palisadal width, palisadal length, palisadal shape, palisadal branching patterns, palisadal angular orientation, and palisadal spacing. By comparing adjacent palisades and assigned binary values of one or zero to each palisade, a unique resultant number may emerge for purposes of comparison with the stored image information. In order to expose the inferior and superior perilimbal structures adjacent to cornea, the individual may be asked, respectively, to raise or lower the eye and with respect to the superior, in addition to causing the individual to look downward, the lids and forebrow are elevated.
A corresponding apparatus which may include a source of radiation, a detector to receive the reflected radiation and convert the same into an electrical signal containing corresponding acquired image information, may have its output introduced into a processing unit wherein a comparison of the acquired image information with the stored image information is effected. The output of the processor provides, to a human interface, an indication as to whether a match has occurred or not.
It is an object of the present invention to provide a highly specific personal, reliable biometric identification system for identifying individuals.
It is a further object of the present invention to provide such a system which relies on information readily obtainable from portions of the eye of the individual which are not normally visible when the individual is not making a conscious effort to expose these portions.
It is a further object of the present invention to provide such a system that employs palisades inferior to the cornea and superior to the cornea, with the interposed interpalisades also being employed.
It is a further object of the present invention to provide such a system, which may be employed with the benefit of computerized processing.
It is yet another object of the present invention to provide such a system which resists any effort to wrongfully appropriate the security indicia so as to interfere with the efficient functioning of the system.
It is a further object of the present invention to provide such a system which has such a wide range of variables that a computer generated number can uniquely identify an individual out of all other individuals to provide a distinct and reliable identification.
It is a further object of the present invention to provide such a system which avoids interference with accuracy as a result of normal degenerative changes in the eye that occur with age.
It is yet another object of the present invention to employ such a system which can be used in combination with other security techniques and systems in order to enhance reliability.